Conventional ways of converting written non-coded information (NCI) to machine readable form involve scanning the document with an optical beam, such as in optical character recognition (OCR) devices. For background, see the IEEE Special issue on Pattern Recognition, October 1972; or the article -- P. L. Anderson, "OCR Enters Practical Stage" DATAMATION, Dec. 1, 1971. For magnetic ink, at times, as in the case of bank checks, one can read the characters with a magnetic head. A third way of converting printed information, is proposed herein which involves the magnetic transfer of the characters to a soft magnetic material, such as amorphous bubble material. The transfer can be made with the addition of a bias field. Of interest are IEEE Transactions on Magnetics, MAG-5 544 (1969), and the article by A. H. Bobeck, "Magnetic Bubble Domain Device," Paper 5-2, Intermag Conference, 1971.
It is known to copy magnetic master tapes containing conventional coded information thereon on a transfer drum and subsequently on a tape with the application of bias fields. However in these systems both the starting and final records comprise coded information on continuous magnetic tapes, drums, discs and the like.
It is known that in certain magnetic film material, under a bias field, will support circular magnetic domains with magnetization axis perpendicular to the film plane. These circular domains, magnetic bubbles, can be moved by field gradient. The field gradient can be obtained by using the combination of photolithography and an applied field. The application of these devices in memory and storage applications is known.
The present invention provides, in one embodiment, a scanner making use of a bubble plate for transfer of information. Circuits and structures are provided for populating, that is filling the bubble plate initially, feeding a document into close proximity with the plate, establishing a field bias relative to the document and plate which achieves an imaging effect of the information on the document into the bubble plate, thereafter moving the plate away from the document, feeding the document out, and shifting the information contained in the bubble plate to another device, such as a storage unit, or the like. Another embodiment utilizes drum members for the bubble and bias elements and this embodiment can be provided with a toner development adjunct. Such an adjunct could also be provided, if desired, in connection with the plate embodiment.